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Currents and throughflow transport in the Taiwan Strait (TS) are systematically analyzed using a new regional ocean reanalysis dataset (China Ocean ReAnalysis, CORA in brief), recently released by National Marine Data and Information Service (NMDIS) in 2009, covering China's coastal waters and adjacent seas. The total throughflow volume transport through TS presents a seasonal variability with the annual-mean of 1.49Sv. It reaches maximum in summer with mean value of 2.33Sv, while in winter the mean transport falls to 0.78Sv on average. The estimated throughflow transport is in good agreement with the observational results. The comparisons of the results with historical observations and numerical simulations also show that CORA performs well on reproducing the currents and temperature field in TS region. In addition, CORA not only successfully reproduced the known oceanic phenomena in TS such as temperature front, up-wind flow in fall, winter northward flow blocking in Penghu Channel, and the winter anticyclonic eddy located at north of Changyun Rise (CYR), but it also found a new cyclonic eddy in north TS in winter. [ABSTRACT FROM AUTHOR]

Abstract Anchovy recruitment determines fish production and thus the sustainable exploitation of anchovy in the Yellow Sea. Haizhou Bay is a traditional spawning and nursery ground for anchovy. The retention of anchovy in its early life stages appears to be related to observed fronts. Cruises have confirmed that anchovy eggs are distributed in high density patches, particularly in the tidal frontal zone. Front and egg patches shift to the shallow area in the warm season. A diagnostic Hamburg Shelf Ocean Model was applied in the East China Sea and Yellow Sea to simulate the frontal circulation and particle movement, forced by monthly wind speed and measured temperatures. It was observed that the jet along the front and upwelling in the mixed side of the front play an important role in the transport of eggs. Convergence and divergence areas are frequently induced by frontal shear instability and topography potential vorticity balance. Numerical experiments show that tidal mixing and front play an important role to converge particles like eggs. When eggs are caught in the convergence zone they are aggregated into a patch. The convergence zone has good feeding condition for eggs to hatch and larvae to grow. [ABSTRACT FROM AUTHOR]

Oceanic processes such as coastal upwelling and mesoscale eddy, could influence the spatial distribution and environmental behaviors of semi-volatile organic pollutants in the marine environment. Seawater samples were collected from the full-depth water columns from the South China Sea (SCS), and PAH concentrations (∑ 14 PAH) in the continental shelf and the open basin areas were 16-110 and 10-93 ng/L respectively. Results of isomeric ratios and principal component analysis illustrated PAHs' mixed sources (petrogenic and pyrogenic). PAH inventory of the SCS seawater was estimated as 100 ± 58 thousand tons, and the majority of them was stored in the intermediate and deep water masses. Generally, full-depth profiles of dissolved PAHs showed an "enrichment in surface and exhaustion in the deep" pattern, and this might be influenced by the oceanic processes such as coastal upwelling or eddy diffusion. In the cross-shelf area, upwelling could enhance the scavenging efficiency of PAHs on the upper layer, and increase the pollutant concentration in the medium and deep water. While in the open-basin area, PAHs were more likely influenced by the halocline stratification and eddy diffusion, and their vertical fluxes due to eddy diffusion was estimated to be 1.2 × 10 -6  g s -1 . This study highlighted the influences of oceanic processes in transport PAHs in the marginal sea, further study is needed to investigate their seasonal variations related to the monsoon characteristics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)